Table. Cluster detection of sleeping sickness, southeastern, Uganda, 1970–2003.

Interval (cluster)	Districts in most likely cluster	Cluster date	No. observed cases	No. expected cases	Relative risk*	p value	Cluster radius (km)
1970–1975	Mayuge, Bugiri, and southern Iganga	1973–1975	63	8	8.3	0.0001	41
1976–1979	Northwest shift to include northern Mayuge, Iganga, Jinja, and southeastern Kamuli	1978–1979	311	23	13.5	0.0001	29
1980–1988	Wider extent, including Mayuge, Bugiri, Iganga, Jinja, and southern Kamuli	1985–1988	13,943	1,865	7.5	0.0001	45
1989–1997	As above, plus Tororo, Busia, eastern Mukono, southern Kayunga, and southern Pallisa	1989–1992	3,176	869	3.7	0.0001	74
1998–2003 (A)†	Northwestern Iganga (Luuka county) and southern Kamuli	1999–2001	331	26	12.6	0.0001	19
(B)†	Soroti	2001–2003	263	21	12.5	0.0001	22
(C)†	Tororo (Osukulu subcounty)	2001–2002	89	7	12.9	0.0001	6
(D)†	Mukono (subcounties of Buikwe, Buyikwe, Najja, Ngogwe, and Ssi)	1998	50	4	12.5	0.0001	0‡­­

*Observed no. cases/expected no. cases.
†Multiple clusters were identified during 1998–2003. Letters correspond to cluster labels in Figure 8.
­­_­‡Cluster included only 1 observation representing 5 merged subcounties.